Tri谩ngulos CSS y compatibilidad entre navegadores

No use transparente en estilos CSS para formas triangulares:

.wrong-triangle {
content
: "";
width
: 0;
height
: 0;
border
-top: 5px solid transparent;
border
-right: 5px solid transparent;
border
-bottom: 5px solid black;
border
-left: 5px solid transparent;
}
.right-triangle {
content
: "";
width
: 0;
height
: 0;
border
-top: 5px solid rgba(255, 255, 255, 0);
border
-right: 5px solid rgba(255, 255, 255, 0);
border
-bottom: 5px solid black;
border
-left: 5px solid rgba(255, 255, 255, 0);
}

FF genera artefactos (bordes) cuando se usa transparent.